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31.
Vaghela SS Jethva AD Gohil MS Subbarayappa A Gour PM Susarla VS Gadde R Ghosh PK 《Annali di chimica》2003,93(9-10):841-848
A textile dye effluent containing chiefly reactive azo dyes has been treated electrochemically for discoloration and COD (chemical oxygen demand) reduction at different current densities, flow rates and dilution. Experiments have been carried out in a thin electrochemical reactor under single pass conditions using a dimensionally stable catalytic anode (DSA) and a stainless steel cathode. 相似文献
32.
A. Włochowicz C. Ślusarczyk D. Źuchowska Indu Malhotra 《Colloid and polymer science》1990,268(7):618-624
Small-angle x-ray scattering (SAXS) and scanning electron microscopy (SEM) investigations for epoxidized butadiene-styrene (BS) block copolymers were performed. For unepoxidized copolymers, the SAXS curve exhibits a maximum which indicates that the copolymer has heterogeneity domain morphology. Using the standard theory for a two-phase system, mean distances between domains, the correlation length l
p
, and the thickness of the phase boundary were calculated from the SAXS data. It was found that the epoxidation of BS copolymers decreases the ability of the copolymer to separate the individual components. As the content of the epoxide groups increases, the dimensions of the domains decrease until they disappear, the boundary between domains and the matrix becomes less and less definite, and the copolymer composes a homogeneous system. The disappearance of the two-phase structure of the BS copolymers indicates an increase in the compatibility of polystyrene and epoxidized polybutadiene. According to the method of Van Krevelen, the solubility parameters of polystyrene and epoxypolybutadiene were calculated. Small differences between these parameters support the conclusions drawn from the SAXS investigations 相似文献
33.
Co(acac)2·2H2O efficiently catalyzes SnCl2-mediated Barbier coupling in water between carbonyls, including aromatic, aliphatic and α,β-unsaturated aldehydes, ketones, sugars and allyl bromide to afford the corresponding homoallylic alcohols in high yields. The catalyst was reused for several cycles with consistent activity. 相似文献
34.
Summary Organometallic compounds of general formula (SCN)2M(NCSeHgR)2 (M=CoII, NiII, R=n-C5H11,i-C5H11) have been prepared. They behave as Lewis acids, forming complexes with pyridine and 2,2-bipyridyl, characterized by elemental analysis, molecular weight, molar conductance, i.r. spectral (4000–200 cm–1), electronic spectral and magnetic susceptibility measurements. The Lewis acids are monomeric with bridging thiocyanate, or selenocyanate between M2+ and Hg2+. Cobalt and nickel acquire tetrahedral and octahedral configurations respectively through axial bridging, whereas mercury retains its linearity. Pyridine links to the metal in the Lewis acid and forms L2(SCN)2M(NCSeHgR)2 complexes. Bipyridyl ruptures the NCX bridge and forms cationic-anionic [M(bipy)3][(NCS)(NCSe)HgR]2 complexes. 相似文献
35.
Parameters are developed for a practical application of the empirical van der Waals (vdW) correction infrastructure available in the CPMD density functional theory (DFT) code. The binding energy, geometry, and potential energy surface (PES) are examined for methane, ethane, ethylene, formaldehyde, ammonia, three benzene dimer geometries, and three benzene–water geometries. The vdW corrected results compare favorably with MP2 and CCSD(T) calculations near the complete basis set limits, and with experimental results where they are available. 相似文献
36.
Trushant Lohar Sanjay Jadhav Arjun Kumbhar Ananda Mane Rajashri Salunkhe 《Research on Chemical Intermediates》2016,42(6):5329-5338
An environmentally benign, multicomponent integrated chemical process has been developed for the synthesis of 3,5-dispirosubstituted piperidines by cyclo-condensation reaction of amines, formaldehyde, and dimedone using iron(III) trifluroacetate [Fe(F3CCO2)3] Lewis acid in aqueous micellar medium at ambient temperature (25–30 °C). The heterogeneous solid acid catalyst conveniently promotes this double amino methylation reaction in which six molecules condense in one pot to form six new covalent bonds. The synthesized 3,5-dispirosubstituted piperidines have been screened for their in vitro antibacterial activity using agar well method. Many of these compounds showed satisfactory antibacterial activity as compared to standard drugs against all the bacteria tested. 相似文献
37.
Pyrazolopyrimidine and pyrimidopyrimidine derivatives have shown a wide range of biological activities such as acting as A1 adenosine receptors, kinase insert domain receptor (KDR), Rous sarcoma oncogene (Src), epidermal growth factor receptor (EGFR), antiproliferative, dihydrofolate reductase (DHFR), antimicrobial, antifungal, and lipid peroxidation. Because of this wide range of activities, we have synthesized pyrazolo[3,4‐d]pyrimidines and pyrimido[4,5‐d]pyrimidin‐4‐one derivatives. 相似文献
38.
39.
Triphenylene derivatives with six peripheral chains can make excellent discotic liquid crystals showing great promise in electronic devices. Vanadium oxytrichloride was found to be a novel reagent for the preparation of various triphenylene derivatives. Symmetrically substituted hexaalkoxytriphenylenes were obtained from o-dialkoxybenzenes by oxidative trimerization with VOCl3 in high yields. Oxidative coupling of a 3,3',4,4'-tetraalkoxybiphenyl with 1,2-dialkoxybenzenes yielded unsymmetrically substituted derivatives of triphenylene; a direct coupling of a 3,3',4,4'-tetraalkoxybiphenyl with alkoxyphenol produced monofunctionalized triphenylenes. 相似文献
40.